Loop Applicator for Chub Machine

ABSTRACT

An apparatus for attaching a loop to the end of a chub package formed by a chub machine. The apparatus includes a drive sprocket and variable speed drive motor for feeding a roll of loops to a clipping head assembly of the chub machine and positioning the loops sequentially for capture by the wire to be cinched around one end of the chub package. A chub machine incorporating the loop attachment apparatus is provided for forming chub packages have a loop attached under the clip at one end of each package. A method for attaching the loop to chub packages is also provided.

CROSS REFERENCE TO RELATED APPLICATIONS

Pursuant to 37 C.F.R. §1.78, this application claims the benefit of andpriority to prior filed co-pending application Ser. No. 10/833,521,filed Apr. 28, 2004, which is expressly incorporated herein byreference.

FIELD OF THE INVENTION

This invention relates to an apparatus and method for feeding a loop ortie in a clip attachment apparatus, also referred to as a chub machine.

BACKGROUND OF THE INVENTION

Chub machines are well known in the packaging industry, and can be usedfor many flowable or extrudable materials. For example, various edibleproducts such as ground meat, cheese, liver sausage, butter, ice creamand cookie dough have been packaged utilizing the chub machines.Inedible products have also been packaged utilizing the chub machines,including explosives.

In operation, a chub machine continuously unwinds and forms a tube froma roll of film, fills the tube with a flowable material, gathers orconstricts at regular intervals short lengths of the filled tubing,applies a pair of closure clips to each gathered length of tubing, andsevers the gathered or constricted material between the individual clipsin a pair thereof. In one type of chub machine, two strands of wire fromcoils or reels are unwound and cut off at predetermined lengths from theends of the wires so as to provide the clips, which are then suitablyformed and constricted in pairs to each gathered length of tubing. Inanother type of chub machine, preformed clips are used.

The primary operating components or elements of a chub machine are: thetube-forming mechanism whereby a web of film is withdrawn from a supplyroll, folded over around a hollow mandrel into a tube and heated orotherwise sealed; a product metering pump which injects flowable productthrough the mandrel out into the tube; a tube or film feed mechanismwhich continuously feeds the tube over and away from the mandrel; avoider which flattens or collapses short lengths of the filled tube atpredetermined intervals; and a clipping head which applies a pair ofspaced clips to the voided and gathered tube and severs the tubeintermediate the clips. These operating components or subassemblies maybe manually operated, or the chub machines may be provided withautomatic control and monitoring systems, such as that set forth in U.S.Pat. No. 5,241,800 to Steinke et al., incorporated by reference hereinin its entirety.

An example of a chub machine having automatic control is provided inFIG. 1. The chub machine, as indicated generally at 5, will berecognized by those familiar with chub machines as having a film arbor6, a mandrel 7, a tube seam overlap heat sealer 8, a product deliverypump 9, a film drive 10, a voider 11, a clipping head assembly 12, awire feed/cut-off assembly (not shown) carried by the clipping head, anda drive mechanism (not shown) housed in the base 13 of the machine. Asis well known to those familiar with chub machines, conventionally, aweb 14 of packaging film is continuously withdrawn from the arbor 6 whenthe machine 5 is in operation. The web 14 is led to a film folder 15where the film is folded and its side edges overlapped thereby formingthe web into a tube surrounding the mandrel 7. The sealer 8 acts to heatseal or otherwise bond the overlapped edges thereby completing theformation of a continuous tube. The film drive 10 engages the exteriorof the tube and serves to continuously feed the tube downwardly. Belowthe film drive mechanism 10 the tube receives a metered quantity offlowable product through the mandrel 7. On passing through the voider 11the voider rolls, at predetermined intervals, depending on the length ofthe packages being formed, momentarily swing inwardly togethercompressing the product-filled tube and thereby substantially voiding orexpelling product from a short length of tube which has been flattenedbetween the voider rolls. Each voided length of the tube is gathered inthe clipping head 12 and a pair of vertically spaced clips applied tothe gathered tube. The lower clip completes the formation of the upperend of one chub package while the upper clip forms the lower end of thenext package. Immediately following the application of the clips areciprocating knife severs the tube midway between the clips therebyallowing the completed chub package P to exit the machine.

Referring further to FIG. 1, the automatic control and monitoring systemcomprises: a pump drive servo 20 operatively connected to the productdelivery pump 9; a film drive servo 21 is operatively connected to thefilm drive 10; and a clamp drive servo 22 is operatively connected tothe clipping head 12. A machine controller 23 in the form of amicroprocessor or computer of known commercial type is a key componentof the control and monitoring system.

Inputs to the controller 23 are connected in signal receivingrelationship to the servos 20, 21 and 22 and also to the heat sealer 8and voider 11 as indicated. Three outputs of the controller 23 areconnected to three servomotor controls 24, 25 and 26 of known commercialtype which are in turn connected in signal delivering relationship tothe servos 20, 21 and 22, respectively, as diagrammatically indicated.

Another output of the microprocessor controller 23 is operativelyconnected to a display 27, which is housed in a custom designed operatorinterface membrane panel 28. The monitor 27 serves as a computer displaywhich enables the operator to effectively manage high levels ofproduction from the chub machine 5 using easy to read symbolic keys onthe membrane panel, multiple language screen displays and memory storageregisters for various product operating presets. There may also beincluded a full range of screen displayed alarms and diagnostics toensure minimum down time. Thus, the various components of the chubmachine, such as the product delivery pump, tube or film feed, film heatsealer, voider and the clamping mechanism of the verticallyreciprocating clipping head may all be automatically controlled by meansof servo actuators operatively connected to a microprocessor.

It is often desirable to insert a loop or tie under one of the clips ofa chub package to support or hang the filled chub package on a rack orhook for further processing, such as smoking, cooking or the like, orfor display. It is also desirable to automate the operation ofpositioning a loop or tie in the pathway of the metal clip prior toapplication of the clip. Various methods and apparatuses have beendesigned for accomplishing loop attachment. One such mechanism isdisclosed in U.S. Pat. No. 5,755,022, which is incorporated by referenceherein in its entirety. Despite these attempts, there remains a need foran improved mechanism for feeding loops to chub packages in a chubmachine, including a loop attachment accessory that may be added to anexisting chub machine without interfering with the operation of the chubmachine.

SUMMARY OF THE INVENTION

The present invention provides a loop attachment apparatus for use witha chub machine for attaching loops to chub packages. To that end, in oneembodiment, a variable speed drive motor and a drive sprocket comprisinga plurality of drive pins operate to advance a carrier strip having aseries of spaced loops attached thereto forward to a clipping headassembly of a chub machine. At the clipping head assembly, each loop issequentially advanced and positioned to be threaded by one of a pair ofadvanced wires, either prior to or after formation of the wire into apreformed clip. The loop is thereby captured by the clip upon securingthe clip to a gathered portion of a packaging tube to close the tube andthereby form the chub package. A cutting knife is also provided to cutthe carrier strip between loops to release each loop as the wire clipengages the loop. The carrier strip is provided with feed holes thatmesh with the drive pins to facilitate the registered motion of thecarrier strip. In an exemplary embodiment, a sensor is positioned inalignment with the drive pins on the drive sprocket to allow registeredfeed of the carrier strip and loops via sensor pick-up of the drivepins. In a further exemplary embodiment, a mounting shaft is providedfor supporting a roll of the carrier strip and facilitating feed of thecarrier strip to the drive sprocket. In yet a further exemplaryembodiment, the variable speed drive motor, for example a servomotor, isprogrammed to over-feed the carrier strip beyond the registeredposition, and then back the carrier strip up to position the open leadloop in the registered position to allow the wire to pass through theopen loop.

The present invention further provides a chub machine including thecomponents of the loop attachment apparatus in addition to means forforming packaging material into a tube and for feeding the tube, meansfor filling the tube with product, a clipping head assembly with a wirefeed and cutting device for applying wire clips to a voided and gatheredsection of the tube, and a cut-off knife for severing the tube betweenwire clips. By virtue of the loop attachment apparatus, the chub machinecontinuously forms chub packages with each having a loop captured by thewire clip at one end of a package or series of packages to enablehanging of the chub packages.

The present invention further provides a method for attaching a loop toa chub packing, including feeding material into a packaging tube,intermittently forming void portions in the tube and gathering the voidportions in a clipping head assembly, feeding wire clips to the gatheredportion and capturing a loop with one of the wire clips to attach theloop to the end of the chub package as the end is closed off with thewire clip. To enable the loop to be captured by the wire clip, themethod further includes feeding a carrier strip having loops attachedthereto in registered motion to the clipping head assembly via aservomotor and drive sprocket with drive pins that intermesh with feedholes on the carrier strip and sequentially positioning each loop in aregistered position for threading by the wire clip. As the wire clipengages the loop, the carrier strip is cut between that loop and thenext spaced loop. In an exemplary embodiment, the method furthercomprises detecting each drive pin with a sensor and feeding a signal toa controller, such as a PLC, to drive the feed of the carrier strip inregistered motion. The method may include feeding wire to the clippinghead assembly, threading the wire sequentially through the loops, andthen cutting the wire and forming it into clips to be applied to thechub packages. Alternatively, the method may include feeding preformedclips to the clipping head assembly to engage the loops and then closeoff the chub packages.

Additionally, the present invention includes a method of modifying anexisting chub machine to include the loop attachment apparatus andassociated benefits of this invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention and,together with a general description of the invention given above, andthe detailed description given below, serve to explain the invention.

FIG. 1 is a diagrammatic view of a chub machine of the prior artincorporating an automatic control system.

FIG. 2 is a perspective view of a loop attachment apparatus for use witha chub machine in accordance with the present invention.

FIG. 3 is a detailed view of the drive sprocket, chain and sensorassembly for the loop attachment apparatus of the present invention.

FIG. 3A is a detailed view depicting sensing of the drive pins of thedrive sprocket and the cutting knife operation for severing the leadloop from a roll of loops.

FIG. 4 depicts a portion of a roll of loops attached to a carrier stripfor use in the apparatus of the present invention.

FIG. 5 depicts capture of the lead loop by a metal clip for attachmentto a chub package in accordance with the method of the presentinvention.

FIG. 6 depicts a loop captured by a metal clip secured to one end of achub package.

DETAILED DESCRIPTION

The apparatus, chub machine and method of the present invention providesautomated, controlled and efficient attachment of loops under the clipsof chub packages to allow vertical hanging of the packages for furtherprocessing and display.

Referring to FIG. 2, a loop attachment apparatus, generally indicated at30, is depicted in perspective view for use with a chub machine, such asthe type of machine depicted in FIG. 1. Apparatus 30 includes a shaft 32upon which may be mounted a roll of loops 34 for attachment to chubpackages. By way of example, a roll of loops 34 may include a carrierstrip 36 having a plurality of loops 38 attached thereto, andadvantageously evenly spaced along the carrier strip 36, with each looppositioned in correlation with a feed hole 40. In an exemplaryembodiment, an open-ended housing 42 (or canister) is provided with theshaft 32 mounted in the center thereof for mounting the roll 34 andfacilitating its feed to the chub machine. The carrier strip 36 is fedthrough a guide mechanism 44, which may also be adjusted to providetension to the carrier strip feed. A sensor 45 may also be provided, forexample associated with the guide mechanism 44, to sense when the end ofthe roll 34 has been reached. The carrier strip 36 passes over a drivesprocket 46, which is connected by roller chain 48 to a variable speeddrive motor 50. In an exemplary embodiment, the drive motor 50 is aservomotor, which is capable of quick speed changes useful in thepresent invention. A sensor 52 is positioned to sense advancement of thedrive sprocket to enable feed of the carrier strip in a registeredmotion. Carrier strip 36 is fed from the drive sprocket 46 to a cuttingknife assembly 54 for engagement of the carrier strip 36 by areciprocating knife blade 56 to release a lead loop from the carrierstrip 36, as will be described in greater detail below.

Referring to FIGS. 3 and 3A, which depict in greater detail the feed andcut mechanisms for the loop attachment, the chain 48 engages the drivesprocket 46 to rotate the drive sprocket, thereby feeding the carrierstrip 36 forward. The drive sprocket 46 includes a plurality of drivepins 58 for engaging or intermeshing with the feed holes 40 on thecarrier strip 36. FIG. 3A depicts a drive sprocket having 8 drive pinswith a 45° net index, though the invention is not so limited. Thespacing of the feed holes 40 and of the drive pins 58 should becorrelated, as necessary, to ensure engagement of the carrier strip 36by the drive sprocket 46. Sensor 52 is positioned in alignment with thedrive sprocket 46 so as to sense the presence of each drive pin 58 whenthe pin comes into alignment with the sensor 52 as the drive sprocket 46is rotated. The drive motor, e.g., servomotor 50 depicted in FIG. 2, anda PLC, e.g., a servo controller (not shown), receive a signal from thesensor 52 that the next successive drive pin 58 is in position, suchthat the drive sprocket 46 can be advanced in registered motion. In anexemplary embodiment, sensor 45 also detects the end of the carrierstrip and signals the controller that the end of the roll 34 has beenreached such that the process may be halted to enable a new roll ofloops 34 to be mounted on the shaft 32.

The feed holes 40, although not visible in FIGS. 3 and 3A, are engagedby the drive pins 58 to feed the carrier strip 36 forward to the cuttingknife assembly 54. The carrier strip 36 is fed into the cutting block 60to advance a lead loop 62 past the reciprocating cutting knife 56 suchthat the knife 56 can engage the carrier strip 36 between lead loop 62and a next successive loop 64 to cut the strip 36 and release the leadloop 62 from the carrier strip 36. Just before the strip 36 is cut, wire66 is threaded through lead loop 62 to capture the lead loop 62. Thus,upon sensing a drive pin 58, the sensor 52 signals the servomotor 50 andcontroller (not shown) to pause the rotation of the drive sprocket 46,whereby the motion of the carrier strip 36 pauses briefly as the wire 66captures the lead loop 62 and as the carrier strip 36 is cut to releasethe now captured lead loop 62. In an exemplary embodiment, the lead loop62 on the carrier strip 36 may be overfed and jerked back into theregistered position to ensure that the lead loop 62 is open forthreading wire 66 therethrough. This may be advantageous for flexiblestring loops passing through a narrow cutting knife assembly passagewhere the loop opening may become distorted. The jerking or reversemotion of the carrier strip 36 allows a distorted loop to straightenback to its original open shape in free space for threading by the wire66. Upon cutting the lead loop 62 free, the drive sprocket 46 is againadvanced until the sensor 52 senses the next drive pin 58. Thus, in anexemplary embodiment, each feed hole 40 is aligned with a loop 38 andeach feed hole 40 is engaged by a drive pin 58 such that each registeredadvancement of the drive sprocket 46 represents an advancement of oneloop 38.

As shown in FIG. 4, an exemplary carrier strip 36 may be a two-ply stripthat captures the loops 38, such as a corded or string loop, between theplies to position the loops 38 perpendicular to the length and feeddirection for the carrier strip 36. Each loop 38 has a loop end 38 a anda tie end 38 b with the loop being attached to the carrier strip 36closer to the loop end 38 a leaving an open portion sufficient for thewire 66 to be fed through at the loop end 38 a. Advantageously, the feedholes 40 are positioned inside each loop 38. After the loop 38 isattached under the clip of a chub package, the two-ply strip may beremoved from the loop.

As depicted in FIG. 5, as the filled tube 70 is fed continuouslydownward with a gathered void portion 72 formed by the voider 11 (seeFIG. 1) positioned in the clipping head assembly 12 (see FIG. 1), thewire 66 of one of the metal clips 74, 76 is threaded through the openingat the loop end 38 a of the lead loop 62 and the carrier strip 36 is cutalong cut line 78 between lead loop 62 and the next successive loop 64so as to release lead loop 62 from the carrier strip 36. A clip formingassembly (not shown) may be included to form and cut a straight wire 66fed from a wire spool (not shown) into a U-shaped clip 74 before orafter, advantageously after, wire 66 is threaded through the loop end 38a, or wire 66 may be in the form of a preformed U-shaped clip deliveredto the clipping head assembly 12 prior to capturing the lead loop 62.The clip 74 with the lead loop 62 captured thereby is then clippedaround the void portion 72 of the tube 70 to clip off the tube with theloop 62 attached under the clip 74, as shown in FIG. 6. The tubematerial is severed at cut line 80 between the two metal clips 74, 76 toform opposing ends of two chub packages P.

In operation, and in reference to FIGS. 1-6, the method of the presentinvention includes mounting a roll of loops 34 on a shaft 32 and feedingthe carrier strip 36 through a guide mechanism 44 and into mesh with thepins 58 of the drive sprocket 46. The feed holes 40 on the carrier strip36 allow positive registered feed via sensor pick-up of the drive pins58 by sensor 52. The lead loop 62 on the carrier strip 36 is fed throughthe cutting knife assembly to a registered position at the clipping headassembly 12. The lead loop 62 may be overfed past the registeredposition, and then reversed to return to the registered position toensure the loop is open. A pair of wires 66 from wire spools are thenfed to the clipping head assembly 12 and one of the wires 66 is threadedthrough the opening of the lead loop 62. The carrier strip 36 is cut torelease the lead loop 62 and the pair of wires 66 are cut. The severedwires are shaped into U-shaped clips 74, 76 with one of the clips 74having the loop 62 captured thereby. While the carrier strip 36 is beingfed and the lead loop 62 is being captured, a packaging film 14 is beingformed into a tube, fed through the chub machine 5, and filled withflowable material to form filled tube 70. The voider 11 creates voidsections 72 intermittently along the tube 70 and each void section 72 issequentially placed in the clipping head assembly 12. Gathering plates(not shown) sequentially gather each void section 72 therebetween andthe clips 74, 76 and captured loop 62 are transferred to the section 72in spaced relation and cinched around the section 72 so as to close offthe tube 70. The cinching action permanently attaches the lead loop 62under the clip 74 at the end of the chub package P. The tube 70 is thensevered between clips 74 and 76, allowing one completed chub package tofall free. In an alternative embodiment, the wire feed, wire cutting andU-shaped clip-forming steps are replaced with the feeding of preformedU-shaped clips 74, 76 to the clipping head assembly 12 with one of theclips 74 capturing the lead loop 62 prior to transfer to the section 72for cinching.

After the tube 70 is severed, the next void section 72 is fed to theclipping head assembly 12, the drive sprocket 46 is rotated until thenext drive pin 58 is sensed, the next spaced loop 64 becomes the leadloop 62, which is then threaded by wire 66, and the next pair of wireclips 74, 76 and captured loop 62 are transferred to the section 72 tobe cinched. The process continues in this registered fashion until thesensor senses the end of the roll 34, or until another feed is depleted,such as the film feed, the product feed, the wire feed, or the preformedclip feed, or until a controller signals the cycle to stop. It may beappreciated that the various operations of the chub machine, as well asthe loop attachment apparatus, may be implemented with any of varioustypes of variable speed drive motors. While a servomotor has beendescribed in the embodiments herein, the various components, includingpump 9, film drive 10, clipping head 12, and drive sprocket 46, may alsobe operated by variable frequency drive motors, variable pulley drivemotors, variable speed dc drive motors or any other type of variablespeed drive motor. These components may be operated by the same type ofmotor or they may each have different types of motors. The drive motorsare advantageously each controlled, for example by a PLC.

While the present invention has been illustrated by the description ofone or more embodiments thereof, and while the embodiments have beendescribed in considerable detail, they are not intended to restrict orin any way limit the scope of the appended claims to such detail.Additional advantages and modifications will readily appear to thoseskilled in the art. The invention in its broader aspects is thereforenot limited to the specific details, representative apparatus and methodand illustrative examples shown and described. Accordingly, departuresmay be made from such details without departing from the scope or spiritof the general inventive concept.

1. A method for attaching a loop to a chub package, the methodcomprising the steps of: feeding a packaging tube; feeding a flowablematerial into the packaging tube; intermittently forming short lengthsof tube void of product; feeding the tube containing the flowablematerial through a vertically reciprocating clipping head assembly tosequentially position each short length between opposing sets ofgathering plates carried on horizontally reciprocating support cams andsequentially gathering the short lengths of the tube therebetween;feeding a carrier strip having a plurality of spaced feed holes and aplurality of loops attached to the carrier strip with each looppositioned in correlation with a respective feed hole from a mountedroll to a drive sprocket that is driven by a variable speed drive motor,the drive sprocket having a plurality of spaced drive pins for engagingthe carrier strip, and then feeding the carrier strip to the clippinghead assembly in registered motion to position a lead loop sequentiallyin a registered position; feeding a pair of wires to the clipping headassembly in spaced relation and sequentially threading one of the wiresthrough each lead loop in the registered position; sequentially cuttingthe pair of wires and wrapping each pair of cut wires around arespective short length to form a pair of spaced wire clips for closingthe tube and sequentially cutting the carrier strip between each leadloop and a next spaced loop to release each lead loop from the rollwhereby each lead loop is captured by one of the pair of spaced wireclips; and severing each short length between the spaced wire clips. 2.The method of claim 1 further comprising detecting each drive pinsequentially with a sensor and feeding a detection signal to acontroller to drive the feed of the carrier strip in registered motion.3. The method of claim 2 further comprising sensing an end of the rolland signaling the controller to stop the steps.
 4. The method of claim 1further comprising feeding the carrier strip in registered motion toadvance the lead loop forward to an over-fed position past theregistered position and then reversing the feed to return the lead loopbackward to the registered position to be threaded by the wire.
 5. Amethod for attaching a loop to a chub package, the method comprising thesteps of: feeding a packaging tube; feeding a flowable material into thepackaging tube; intermittently forming short lengths of tube void ofproduct; feeding the tube containing the flowable material through aclipping head assembly to sequentially position each short lengthbetween opposing sets of gathering plates carried on horizontallyreciprocating support cams and sequentially gathering the short lengthsof the tube therebetween; feeding a carrier strip having a plurality ofspaced feed holes and a plurality of loops attached to the carrier stripwith each loop positioned in correlation with a respective feed holefrom a mounted roll to a drive sprocket that is driven by a variablespeed drive motor, the drive sprocket having a plurality of spaced drivepins for engaging the carrier strip, and then feeding the carrier stripto the clipping head assembly in registered motion to position a leadloop sequentially in a registered position; feeding a pair of preformedwire clips to the clipping head assembly in spaced relation andsequentially threading one of the wire clips through each lead loop inthe registered position; sequentially attaching each pair of spaced wireclips around a respective short length to close the tube andsequentially cutting the carrier strip between each lead loop and a nextspaced loop to release each lead loop from the roll whereby each leadloop is captured by one of the pair of spaced wire clips; and severingeach short length between the spaced wire clips.
 6. The method of claim5 further comprising detecting each drive pin sequentially with a sensorand feeding a detection signal to a controller to drive the feed of thecarrier strip in registered motion.
 7. The method of claim 6 furthercomprising sensing an end of the roll and signaling the controller tostop the steps.
 8. The method of claim 5 further comprising feeding thecarrier strip in registered motion to advance the lead loop forward toan over-fed position past the registered position and then reversing thefeed to return the lead loop backward to the registered position to bethreaded by the wire clip.